Art of tipping laces



Feb. 25, 1941,.

K. H. ANDREN ART oF TIPPING LAcEs Filed March 5, 1939 4 Sheets-Shag?, l

ATTORNEY Feb. 2 5, 1941. K, ANDREN l 25233121 ART 0E TIPPING LAcEs FiledMarch 3, 1939 4 Sheets-'Sheet 2 l IEIVENTOR ATTO NEY'.

Feb. 25, 1941.

K. H. ANDREN ART 0F TIPPING-LACES Filed March 3,A 1939 4 Sheets-Shea?l 3Patented Feb. 25, 1941 vPATENT OFFICE ART OF TIPPING LACES Karl H.Andreu, Milwaukee, Wis., assignor to Artos Engineering Company,Milwaukee, Wis., a corporationof Wisconsin l Application March s, 1939,serial N01. 259,618'

9 Claims.

The present invention relates to improvements in the art of applyingtips to shoe laces `or the like, and relates more specifically toimprovements in the construction and operation of mechanism for,applying so-called fiberor Celluloid tips to cords or laces.

Generally defined, an object of my present invention is to provide a newand useful method `of insuring effective application of tips formed ofrelatively soft and pliable material to shoe laces or the like, atrelatively high speed and with minimum difculty and Waste.

In the earlier days of the shoe lace manufacturing industry, it wascommon commercial practice to apply metal tips to the lace-s' bywrapping a strip of thin metal about the medial portion of a pieceoflace stock with the aid of cooperating forming dies, and bysubsequently severing the enwrapping metal `centrally so as to producetwo complete tips one of which-Was permanently applied to each of theadjacent ends of the severed lacing. Machines of the type adapted toapply the metal tips in this Vmanner are shown in Swift Patent No.866,314y in Church Patent No. 895,724, and in Armitage Patent No.

1,423,894, and these machines operated quite satisfactorily whenapplying metal tips. During recent years it has been found `moredesirable to apply so-called ber instead of metal tips, `these fibertips being formed of `thin strips `of Celluloid which, however, mustbesoftened with the aid of suitable solvent and must `also be subjectedto heat, in order 'to permit free Wrapping of the tipping material aboutthe laces and to cause the wrapping sheet to. retain its final tubularshape. With the adventfof .these ber or Celluloid tips, many conditionshave arisen to make lace tipping a delicate and difficult operation withthe prior standard machines. It has been found that even after theforming 'dies have been properly set,'and `for various reasons, the tipsfrequently become distorted or misformed, and sometimes open up as theyleave the dies, and in some cases the tipping stock does not overlapsufficiently, "or the sheet material buckles. These detrimental actionstake place because the Celluloid is relatively resilient and is madesoft and pliable by the solvent and heat, and if the dimculty is notquickly discovered and corrected While the tipping, machine isoperating, considerable damage may result and much stock will be wasted.While these difficulties are not so pronounced and serious in slow handoperated machines, they becomev vital in the `operation of high speedlace tipping equipment and preclude the productionof a succession ofperfect lace tips.

I have discovered that correct curvature of the forming surfaces of the`dies, is important in the production of perfect Celluloid tips, and ifthe 15 die curvature and stock stops are not correct, the Celluloidstrip Will at times be improperly wrapped about the lace, thus resultingin defective tips. Then too, I have found that since the prior formingdie assemblages have no means l0 for controlling the action of therelatively moving `tip forming dies, they do not function to uniformlycompress thesuccessive laces While the Celluloid strip is being Wrappedtherearound to the desired extent, so that uniform overlap is not 15obtainable with these prior structures'. As a result of `this omission,the forming slide` of the Vdie often starts too quickly and prevents thetrailing end of the strip from being tucked in `properly,o`r it `doesnot start soon enough so `that they leading edge of the strip Will beWrapped around the tip and instead will be sheared ofi. In either case,imperfect tips are produced, and continued operation of the machineafter one defective tip has been formed invariable results Vin theproduction of other subsequent faulty tips and precludes formation ofuniformly perfect product at commercially satisfactory speeds.

It' is therefore a more specific object of my present invention toprovide instrumentalities Wherebyuniform and perfect successive tips maybe produced automatically and at relatively high speed.

Another specific object of the invention is to provide an improved lacetipping die assemblage having properly curved and cooperating tipforming surfaces which Will insure proper -wrappingand tucking of thetip producing material.

A further specic object of the present invention is to provide improvedmeans for controlling the movement of a pair of` relatively movable tipforming dies so that uniform application of successive tips is assuredat all times. Still another specific object of my invention is toprovide a method of applying perfect Celluloid tips to successive laceswith the aid of automatically functioning dies and at high speed, withminimum Aattention and at relatively low cost..

These and other specific objects and advantages will be apparent fromthe following detailed description. l

Aclean conception of thel several steps constitutng my improved mode ofapplying tips to laces, and of the construction and operation of amachine especially adapted to tip shoe laces, may be had by referring tothe drawings accompanying and forming a part of this specificationwherein like reference characters designate the same or similar parts inthe various views.

Fig. 1 is a longitudinal vertical section through one of my-improvedshoe lace tipping die assemblages, showing the same applied to afragment of the frame of a shoe lace tipping machine;

Fig. 2 is a side elevation of the die assemblage of Fig. l showing therelative location of the shaft which carries the lace conveying spiders;

Fig. 3 is a top view of the forming die assemblage of Figs. 1 and 2;

Fig. 4 is an end view of the same die assemblage;

Fig. 5 is a transverse vertical section through the lace tippingmachine, taken along the line 5 5 of Fig. 1;

Fig. 6 is a similar transverse vertical section through the machine,taken along the line 6-6 of Fig. 1;

Fig. 7 is another transverse vertical section through the dieassemblage, taken along the line 1 1 of Fig. l; v

Fig. 8 is a perspective View of a shoe lace tipping machine having oneof my improved dieassemblages in operative position therein, and anothersuch assemblage positioned upon the frame thereof;

Fig. 9 is an enlarged diagrammatic section of my improved forming dieassemblage showing the same in the initial position during applicationof a tip forming strip to a lace;

Fig. 10 is a similar view showing the movable die approaching thenormally stationary die, and the tip stock severed from the supplysource and initially conned between the dies;

Fig. 11 is another similar view showing the movable die advancedsuiiciently to urge the tip stock against the other die and to initiallybend the stock, and also showing the lace partly compressed;

Fig. 12 is an additional similar view showing the next step of the tipforming and applying process;

Fig. 13 is a similar view to a reduced scale, showing the position ofthe die assemblage while the movable die is completing the inner endtuck and the other die is still in xed position;

Fig. 14 is another enlarged similar view of the die assemblage showingthe tip formation just prior to nal completion;

Fig. 15 is a View similar to Fig. 14 showing the completion of a tip;

Fig. 16 is a more complete section similar to that of Fig. l, butshowing the forming dies moved to the position shown diagrammatically inFig. 9;

Fig. 17 is a view similar to that of Fig. 16 but showing the formingdies in the same position as in Fig. 14; and

Referring specifically to Figs. 1 to 8 inclusive of the drawings, thestandard shoe lace tipping machine shown therein comprises in general amain frame 20; a horizontal rotary shaft 2| journaled in the frame 20; apair of laterally spaced lace clamping spiders 22 mounted upon themedial portion of the shaft 2|; a pair of lace conveying spiders 23adjustably secured to the shaft 2| outwardly beyond the spiders 22; areciprocable shuttle 24 slidable along the frame 20 and adapted tosupply a continuous strand of lacing stock 25 to the arms of the spiders22, 23 during revolution of the latter; solvent applying means 26coacting with the successive lace sections between the spiders 22 andabove the shaft 2|; a forming d-ie assemblage disposed upon the frame 20laterally adjacent the mid-portion of the shaft 2| and between thespiders 22; and an actuating shaft 21 for the forming dies alsojournaled in the frame 20 and having thereon cams which are housedwithin a casing 28. The solvent applying means 26 are carried by frame20 and by a bracket 29 secured to the casing 28 and upon which a solventsupply reservoir 30 is also mounted, and the frame 20 is also providedwith an electrical control element 3| near the tipping zone, and withfeed mechanism 32 for intermittently feeding a strip of Celluloid stock33 into the zone of action of the forming dies during normal operationof the tipping assemblage. All of these elements are of old andrelatively well known construction as indicated by the prior patentshereinabove referred' to, except that the die assemblage is of improvedconstruction.

My present improved die assemblage which is associated with the mainframe 20 between the clamping spiders 22, comprises in general a base 34having a central opening for permitting delivery of the Celluloid stock33 upwardly therethrough; an elongated work support 35 and an adjacentsimilarly elongated forming block 36 secured to a plate 31 which ismounted upon the y base 34; a pair of relatively movable but normallystationary laterally adjoining forming dies 38, 38' resting upon saidIblock 36 and plate 31;

and a pair of relatively displaceable and simultaneously movablelaterally adjoining forming dies 39, 39 carried by slide members 40, 46which are slidably mounted upon the base 34. The base 34 has one or moreelectric heating elements 4| therein which are cooperable with thecontrol element 3|; and also has a transverse end plat'e 42 rigidlyattached thereto, this end plate 42 being provided with set screws 43which are coop-4 erable with the adjacent end of the die supportingplate 31 in order to accurately initially position the work support 35and the forming block 36 attached to the plate 31. The control element3| is insulated to accurately gauge the heat of the. bottom of base 34,and cooperates with switch mechanism in a well known manner, and theentering Celluloid stock is protected against excessive heat by aninsulating guide 44 the upper end of which coacts with the end of theplate 31' near the work support 35. 'I'he opposite sides of the frame34, are provided with special adjustable guides 45 for steadying andeliminating vibration of the lace stock 25 as the successive sectionsare positioned upon the work support 35 by the revolving clamping andconveying spiders 22, and the upper edge portion of the forming block 36adjacent the work support is provided with a chamfer 46 as clearly shownin Figs. 9( to 15 inclusive.

The cooperating faces of the 4forming dies 38," 38', 39, 39 arepreferably,accuratelycurved as illustratedin Figs. 9` to-15inclusiveiand the normally stationary dies 38, "38" are provided withstops 41 which are cooperable with-the overlapping portions 49 ofthesmovable'dies 39, 39 V:to

prevent damaging ,of thegsharp anddelicate die i edges when the machineis operating and nonlace and tip stock is being supplied. 1,- Tl'leforming dies 39, 38 are secured to slides 49, 49 respectively, which areslidably confined in the base 34 and each of whichhas a 1ug59fmovablebetween limit stop `screws 5I, 52,- but-movement of the slides 49, 49and dies 38,'38'vaway` from the work sup- `port 35` is at all timesrestrained by compression springs 53 coacting withthe slides 49, 49through in the base 34 by means of top Wedges 51 which `are adjustab-lewiththe aid of set screws. 59, and each member has a driving block 59ad- Ajustably attached to the lower'portion thereof by means of screws99'and locking set screws.` The blocks 59 are adapted to be reciprocatedin prop- Ierly timed relation to eachother, bymeans of reciprocalbleelement's'l 4specifically shown in Fig. 1, andthese elements `6| aremovable by suitable cams carried by the drive shaft 21 shown in Fig. 8,in a manner which will be subsequently described. It isto be noted, thatby adjustingthe relative positions of theblocks 59 and members 49 withthe aid of the screws 69, the movable forming dies 39, 39' Amay beaccurately positioned for proper cooperation with. the normallystatic-nary dies 38, 38', and it is essential thatjthe various partscooperate with minimum necessary clearances so that the dies will alwayscoact .with each other properly. The complete forming die `assemblage isobviously carried bythe base 34 which may be removablyattached tothemain frame 29 in any suitable manner, and convenient .insertion andremoval of the die assemblage may be effected as indicated in Fig. 8,with the aid of eye-bolts 62. In actualcommercial practice,.a

spare die assemblage such as `shown in Fig. 8, is

preferably kept-available sov as totprevent excess `waste of time incasereplacement` of a die unit jbecomes necessary, or yfor quick changeof`inachine to a different size of die fora different lace.

DuringY normal operation of my improved shoe lace tipping mechanism, andwhile carrying on my improved method of applyingtips to thesuccessivelaces, the machine is being driven'so as `to cause the shuttleNte-continuously wind lacing stock 25 about the arms .of theintermittently revolving spiders 23 and through the clamps carried bythearms of the spiders 22. The die assemblage is being operated inunison with the revolving spiders 22, 23, so that successive stretchesof lacek stock are automatically urged past the guides and are.positioned bythe clamping spiders 22 upon thework support 35.` Thesuccessive Steps which follow this positioning of a `section of lacestock 25 uponthe work support 35, are illustrated diagrammatically inFigs. V9

to 15 inclusive, and it will be understood that the feed mechanism 32 isfunctioning to intermittently advance the Celluloid tip stock 33 as theforming dies complete their operations. This stock 33 may be either inthe form of a single strip, or two laterally separated strips.

l Referring specially to Fig. 9, the movable forming die 39 is advancingtoward the stationary die 38 and the lower edge of the die 39 iscooperating with the adjacent upper edge of the work support 35 toshearoff a piece of the Celluloid stock 33 sufficient to form a tip. Thelower edge of the die 39 is in alinement with the chamfer 46, and isheld in this position by the heavy spring 53 against stop means 5I, andthe lace stock 25 is resting uponthework-support 35 somewhat off center.

As the movable die 39 continues its forward movement to the positionshown in Fig. 10, the portion 98 thereof overlaps the die 38 theposition of which remains momentarily unchanged. The die 39 has carriedthe lace stock 25 some distance over the work support 35 and has carriedthe severed piece 33' of Celluloid stock intov contact with the curvedface of the stationary die 39. The die 38 is, however,` maintained inrelatively fixed position by the spring 53.

In Fig. 11 I have shown the movable die 39 advanced still further towardthe relatively fixed die 39. The lace stock 25 has been somewhatcompressed and bulged, and it will be understood that the portion of thelace stock 25 at the zone of application of the tip has been previouslysaturated with solvent by the means 26 which receive their supply ofsolvent from the reservoir 39. In the disclosure of Fig. 11 the section33 of Celluloid stock has been somewhat further distortedand urged intocontact with the upper part of the lace stock 25, and one edge of thestock piece 33 is being forced downwardly around the curved face of thexed die 38. The dies 39 and 39 are so curved in relation to each otherthat the bending ofthe Celluloid always takes place as shown.

Asthe movable die 39 advances to the position illustrated in Fig. l2, itfurther compresses the solvent soaked lace stock 25 and forces the sameinto contact with the Celluloid piece 33' which `or withinthe edge ofthe piece 33 which coacts with the chamfer 46. It is to be noted thatthe end of the member 4s up to this time has not yet engaged theadjacent end of the plunger 54.

In Fig. 14 the member 49 has advanced into contact with the plunger 54Yand the movable die 39 has urged the Celluloid piece 33 into snugcoaction with the curved faces of the dies 39, 38,

`and the downwardly directed end of the piece 33 is about to be lappedover the opposite inwardly tucked edge of this piece.

Subsequent advancement of the member 49 and die 39 carries the lacestoel: 25 away from the chamfer 43 and urges the plunger 54 rearwardlyso ,as to remove the pressure from the heavy spring 53 and allow thecompressed mass of lace and Celluloid to urge the now unloaded slide 49and the die 38 to follow the die 39 as one unit with a fixed spacebetween the edges of same. This movement causes the outer edge of theCelluloid piece 33 to be folded by the stationary folding block 36 intosnug engagement with and over the inwardly tucked edge of the piece 33',thus completing the action of Wrapping the Celluloid strip about thelace stock 25. This action and cooperation of the dies also positivelyprevents the leading edge of the piece 33' from remaining in the notchit and being sheared olf. The mechanism is then automatically operableto cause one set of dies 38, 39' to be arrested by the correspondingstop screw 52, while the complementary set of dies 38, 39 continues itsforward movement against the corresponding screw 52, thereby shearingthe piece of lace stock and the embracing tip, into two parts andproviding a completed tip at each of the adjacent ends of the severedstock 25. When the wrapping operation has been thus completed in aheated Zone, there `is a slight dwell and the solventl with whichthelace stock 25 is saturated will then quickly evaporate and cause thetip to set. The dies 38, 138', 39, 39' are subsequently returned to theposition shown in Fig. 1, and the spiders 22, 23 are revolvedsufficiently to carry another section of solvent soaked lace stock 25into position upon the work support 35. Simultaneously with thisoperation, the severed and tipped lace stock 25 is advanced by and dropsfrom the spiders 22, 23, leaving the bared arms of these spiders freefor the reception of subsequent lacing. In this manner, the successivelaces are automatically tipped and cut into proper length, and aredelivered from the machine, and it has been found practical to operatemachines of this type at eX- `tremely high speed sufiicient to produceas high as 140 laces per minute, without any failures.

From the foregoing detailed description, it will -be apparent that mypresent invention provides extremely simple yet highly eicient apparatusfor rapidly, accurately, and uniformly applying tips to successivelaces, without danger of failures. It will be apparent that the propercurvature of the forming dies is essential, and that the provision ofthe chamfer 15in the forming block 36 is also important. But of primaryimportance is the provision of the plunger 54 and spring 53 whichpermits the dies to relatively adjust themselves Vso as to insureuniformity in the wrapping operation and which eliminate shearing off ofthe leading edge of the tip stock. With my present improvement, it hasbeenA found' possible to uniformly tip the successive laces with minimumfailures and at relatively high speed, and by virtue of the Variousadjustments provided, the mechanism can be readily. set so as to insurecontinued operation throughout long periods of time and with minimumattention. With my improved process, the completion of the tippingoperation and the severing is eiected .after the lace stock has beenremoved from the Work support andthe completion of each operation isactually effected -by rth-e forming block 36. 'Ihe movable die besidesserving to wrap the Celluloid vabout the laces, also functions .as :acutter to remove successive sections of the Celluloid from the supplystrip and sin-ce each of the sections 33' is Iacted upon in preciselythe same manner by the accurately formed ,and specially curved formingdies, uniformity in application yof the tips must necessarily result.'I'he invention has proven highly successful in actual commercial use,and

the structure forv carrying on my improved process is obviously sosimple that it can be manufactured and operated at extremely moderatecost.

It should be understood that it is not desired to limit this inventionto the exact details of construction or to fthe precise steps of theprocess, herein shown and described, for various modifications withinthe scope `of the claims may occur to persons skilled in fthe art.

I claim:

1. The method of wrapping a piece of tip stock about a lace, whichcomprises, confining the piece of tip stock and the lace in acontracting space having curved opposite ends and :an off-set notchadjacent on-e of the ends, contracting rthe space to move one end of thepiece into the notch and into snug coaction with the .adjacent curvedend and simultaneously initially distorting the lacing to patti-allyconform with the interior surface of curved piece, tucking the edge ofthe piece remote from the notch beneath the edge thereof confined Withinthe notch, resiliently restraining the contracting action to which saidspace is subjected, and subsequently moving .the lace and embracingpiece of tip stock away from the notch under the influence of saidresilient restraining force to wrap the outer edge .of the piece snuglyover the tucked end thereof.

2. The method of applying a tip to a lace, which comprises, conning lalace and a piece of tip stock in a, space having relativelyapproacha'ble curved end walls and an off-set notch contiguous with oneof the walls, moving the Walls toward each other While' resilientlyrestraining the contracting action of the coniining space .to initiallycompress the lace and .to force one end of the stock into said notch,tucking the opposite end of the stock between the lace and the endportion confined in the notch, and thereafter moving the fixed coniningspace while still subjected to said restraining force 'away from thenotch rto Wrap said end portion snugly against and over Ithe tucked end.

3. The method of tipping laces, which comprises, Wrapping Ia piece oftip stock about a solvent saturated lace and gradually compressing theenwrapped portion in a space one wall of which is resiliently restrainedby a pressure exceeding the compression force.

4. The method of tipping laces, which comprises, Wrapping a piece of tipstock about a solvent saturated lace and gradually compressing theenwrapped portion in a space one Wall of which is resiliently restrainedby a pressure exceeding the compression force, and thereafter severingthe lace and Wrapping stock to produce segregated independent nallytipped lace ends.

5. In combination, a work support, means forming an offset notch at oneend of said support, a pair of relatively movable dies havingcooperating curved surfaces one of which normally terminates at saidnotch, means for positioning lace stock and tip forming material betweensaid dies, means for relatively moving said dies to Wrap the tip formingmaterial about the stock and to cause said notch forming means tocomplete the Wrapping operation while said dies are definitely spaced,and means for resiliently restraining the approaching movement of saiddies during the wrapping operation.

6. In combination, a work support, means forming an off-set notch beyondone end of said support, a pair of dies relatively movable along saidsupport and having curved approachable surfaces, means for positioninglace stock and a piece of tip forming sheet material between saidsurfaces, means for moving said surfaces toward each other toinitiallywrap said material about said stock and to finally cause saidnotch forming means to complete the wrapping operation under controlledconditions, and means for resiliently restraining the approachingmovement of said surfaces.

7. In combination, a work support, a forming block coacting with saidsupport to provide a notch adjacent to the latter, a normally fixed dieresiliently restrained against movement and having a curved forming facecontiguous with said notch, a movable die having a curved face movabletoward the curved face of said fixed die, said movable die having acutting edge contiguous with its curved face and cooperable with saidwork support to sever sections of tip forming sheet material and todeliver the same between said curved faces, means for positioning lacestock between said curved faces, and means for initially moving saidmovable die toward said curved die and for subsequently moving said diesin fixed relation away from said notch over said forming block to wrapsaid tip forming sections about the lace stock.

8. In combination, a work support, a forming block coacting with saidsupport to provide an intervening off-set notch, a normally fixed dieresiliently restrained against movement away from said notch and havinga curved face contiguous with said notch, a movable die movable towardsaid normally fixed die and having a curved face facing the curved faceof said fixed die, means for feeding lace stock and tip forming materialbetween said faces, and means for relatively moving said dies to causesaid faces to wrap said material about said stock and to cause saidnotch to complete the wrapping operation.

9. In combination, a work support, a forming block coasting with saidsupport to provide an intervening off-set notch, a normally fixeddieresiliently restrained against movement away from said notch and havinga curved face contiguous with said notch, a movable die movable towardsaid normally fixed die and having a curved` face facing the curved faceof said fixed die, means for feeding lace stock and tip forming materialbetween said faces, means for relatively moving said dies to cause saidfaces to wrap said material about said stock and to cause said notch tocornplete the wrapping operation, and means for subsequently relativelymoving portions of said dies to sever the tip and stock.

KARL H. ANDREN.

